With its warm breezes, azure water and swaying palm trees, the tiny island of Tuvalu seems like the perfect tropical hideaway. Yet something is amiss on this speck of paradise halfway between Hawaii and Australia. Global warming is erasing Tuvalu from the map. Within 50 years, if sea levels continue to rise at the current rate, the ocean will completely swamp the 10-square-mile island.

For decades, we've depended on an outdated, centralized power system that wastes power and occasionally fails to meet everyone's needs. The idea of a localized power grid, or microgrid, might just be the change we need.